1. Field of the Invention
This invention generally relates to a photographic camera equipped with a distance measuring optical system and a photograph taking optical system and more particularly to an optical member carrying body disposed in the camera in which the distance measuring optical system is arranged separately from the photograph taking optical system.
2. Description of the Prior Art
In an optical apparatus of the type having a distance measuring optical system separately arranged from a photograph taking optical system, distance measurement is generally based on the principle of a base line range finder.
In this instance, not only it is important that the distance measuring optical system have a sufficient degree of precision relative to the base length thereof but, in order to precisely perform automatic focusing by displacing an optical member within a photograph taking optical system, it is also important to maintain a highly precise positional relation between the photograph taking optical system and a distance measuring optical system. This is particularly so where the camera is provided with an automatic focusing mechanism.
However, in accordance with the conventionally known art, a photograph taking optical system and a distance measuring optical system are provided with separate carrying parts for carrying them. Besides, each of these carrying parts is individually shaped by metal die casting such as aluminum die casting or zinc die casting. They are coupled with each other after a secondary machining process. Then, a photograph taking optical path and a distance measuring optical path are aligned with each other. With a photograph taking optical system and a distance measuring optical system separately shaped from each other in this manner, it has often been hardly possible to obtain a sufficient degree of overall precision. Besides, it has been extremely difficult to maintain the interconnection of the photograph taking optical system and the distance measuring optical system with each other in an adequate degree of precision against ageing changes and environmental changes such as changes in temperature and humidity. Thus, it has been virtually impossible to make highly precise alignment of these optical paths. Furthermore, with these carrying parts coupled with each other after the metal die casting process and the secondary machining process, large expenditures have been necessary for machining and assembling and thus there has been a problem also in terms of economy.